Sheet-handling apparatus



L HOPKINS June 13, 1939.

SHEET-HANDLING APPARATUS Filed Aug. 27, 1938 5 Sheets-Sheet l INVENTGR.L/e wefiyn Hop/fins ATTORNEY.

June 13, 1939. L HOPKINS 2,162,580

SHEET HANDLING APPARATUS Filed Aug. 27, 1938 5 Sheets-Sheet 2 Jiq. z.

INVENTOJQQ. L )e we Hyn Hop/fins BY ATTORNEY.

June 13, 1939. HOPKINS 2,162,580

SHEET HANDLI NG A PPARATUS Filed Aug. 27, 1938 5 Sheets-Sheet sHVVENTUR.

L/ewe/lyn Hop/fins BY 49 Z9 CzujLuoiit llhizl4.

A TTORNEY.

June 13, 1939. L4 HOPKINS 2,162,580

SHEET-HANDLING APPARATUS Filed Aug. 27, 1938 5 Sheets-Sheet 4 INVENTGRQL/e wel/yn Hop/r1713 BY MM mun A TTORNEY.

June 13, 1939. HOPKINS SHEET-HANDLING APPARATUS Filed Aug. 27, 1938 5Sheets-Sheet 5 INVENTGR. Llewe/Zgr; Hop/fins ATTORNEY.

\ Patented June 13, 1939 v UNITED STATES PATENT OFFICE SHEET-HANDLINGAPPARATUS Llewellyn Hopkins, Butler, Pa.

Application August 27, 1938, Serial No. 227,145

17 Claims.

are stucktogether can be discarded and the other sheets deposited onconveyors or the like. One object of my invention is to provide meansfor effectively removing sheets one-by-one from a stack, even thoughthere is tendency of the sheets to adhere together through atmosphericpressure or otherwise.

Another object of my invention is to provide an improved means forfeeding sheets one-by-one from a stack.

A further object ofmy invention is to provide means for automaticallythrowing out or discarding sheets which adhere together during theremoval of the sheets from a stack.

- Still another object of my invention is to provide an apparatus ofgenerally simplified and improved form which will operate rapidly andeffectively in the feeding or sorting of sheets.

Some of the forms which my invention may take are shown in theaccompanying drawings wherein Figure 1 is a longitudinal sectionalvviewthrough the apparatus; Fig. 2 is a cross-sectional view thereof Fig. 3is a view on an enlarged scale taken on the line IlIIII of Fig. 2; Fig.4 is an 0 enlarged view taken on the line IV--IV of Fig, 2; t

Fig. 5 is a view taken on the line V-V of Fig. 4; Fig, 6 is a sectionaldetailed view of a portion of the apparatus of Fig. 1; Fig. 7 is alongitudinal view through one of the separating devices for the'marginal edges of the sheets; Fig. 8 is a view taken on the lineVIII-VIII of Fig. I; Fig. 9 is a view showing the device of Fig. '7 inoperating position; Fig. 10 is a plan tiew of the j separating blade ofFig-7; Fig. 11 is a schematic. view showing the arrangement of thecontrol mechanism for various operating parts of the machine; Fig. 12is, an 'elevationalsectional view of a modified form of sheet-separatingapparatus, and Fig. 13 is a view taken on the line XIII-XIII- 01" Fig.12.

As shown in Fig. *1, a framework II has journailed thereonidler rollers16 along which packs of sheets H are moved to bring the pack intoposition above a table i8. The table I. at its corners carriesdepending-posts l9which telescopically fit within, upright guide members2|.v A screw jack 2| engages the underside of. the table-at its centralportion,,so that the table and the pack carriedthereby can be raisedstep-by-stepduring removal of the sheet from the pack, as hereinafterdescribed. The nut 22 which engages with a jack screw carries a bevelgear wheel 23 with which a pinion 24 meshes. The pinion 24 is mounted ona shaft 25 which carries at its outer end a pinion 23 that meshes with agear wheel 21, the gear wheel being provided with a handle 28 by whichit may be manually turned to initially raise the table and therebyslightly lift the pack I! from the rollers i6.

A series of blades or edge separating devices are provided alongsideeach edge of the pack, in position to operate on the topmost sheet ofthe pack. These separating devices are designated generally by thenumeral 29 and are shown more clearly in detail in 'Figs. 7 to 10. Eachof the separating devices 29 is mounted upon a bar 3li which in turn isadjustably secured to the framework of the machine for adjustment towardand away from the edges of the pack, as shown more clearly in Fig. 2.Each device is mounted upon a supporting plate 3i which is pivotallyconnected at 32 to the bar 30. An adjustable stop screw 33 is providedfor eifecting proper alignment between the device and a pack, a spring34 serving to yieldably hold the separating device against the stopscrew.

The members 29 are allot similar construction and a detailed descriptionof one will suflice for all. A hollow block 35 is secured to the plate3! and. is provided with a removable cap plate 36. A slide block 31 ismovable longitudinally within the block 35 and carries a blade 38havinga sharpened nose portion or knife edge 39, that is adapted to bemoved beneath the topmost sheet of a pack. A roller 40 is journalled inan arm 4i carried by the block 31 and which is pivotally mounted at 42.The roller 40 is positioned slightly in advance of the knife 39 so thatwhen the block 31 is moved from the position shown in Fig. 7 toward thatshown in Fig. 9, the roller will first engage the top of the packandthereafter the blade 39 will pass beneath the top sheet, moving the sameto the position shown in Fig. 9.

In the position shown in Fig. 7; the roller is rigidly held againstraising movement on its pivot. by means of the cap 36. If the verticalposition of arm 4| that carries the roller is clear of the cover plate36, so that when the top sheet is raised, as hereinafter explained, theroller can swing upwardly around its pivot 42 to be thereby disengagedfrom the sheet.

The vertical spacing between the roller 48 and the knife edge 38 isadjusted to correspond with the different sheet gauges, by an eccentric48 upon which the roller 40 is mounted. Rotative adjustment of theeccentric 48 will, of course, raise or lower the roller relative to theknife blade. An extended hub of the cam is threaded to receive a nut 44to clamp it in adjusted positions, the other end of the hub having asquared shank 45 which can be turned by a wrench.

When the blades are entering beneath the top sheet of a pack, blasts ofair are introduced through the blades and beneath the sheet to assist inseparating the sheets and to eliminate suetion which may result when thetop sheet is lifted as will be hereinafter described. To this end. theknives are provided with passageways 46 that discharge at the forwardedges of the knives and at their rear ends communicate with ports 41that have constant communication with passageways-48 formed in the slideblocks 81. A pipe 49, to which air under pressure is supplied,communicates with each passageway 48, the side walls of the hollowblocks 35 having longitudinal slots formed to permitmovement of thepipes 49 with the slide blocks 31. Each slide 31 is reciprocated by apiston contained within an air cylinder 50, fluid pressure beingadmitted and exhausted at the opposite sides of the piston through pipeconnections 5| and 52.

A cross head is provided at each end with slide blocks which arevertically movable in guide ways 56 carried by the stationary framework.The cross head is vertically supported by a pair of connecting rods 51that are hung from crank arms 58 which are formed on a crank shaft 59,the crank shaft 59 being journalled in bearings 60 that are mounted uponcross beams 8|. The crank shaft carries a gear wheel 62 that has meshedengagement with a rack bar 68 formed on the end of a piston rod, that isconnected to a piston within a cylinder 64, fluid pressure beingadmitted through pipes 65 and B6 to the opposite ends of the cylinder toeffect actuation of the crank shaft 59. The cranks 58 are moveddownwardly, thereby moving the cross head 55'downwardly, while admissionof fluid pressure to the opposite end of the cylinder will effectraising movement of the cross head.

Four pairs of vacuum cups 61 are provided. Each pair of cups is mountedon extensions of a yoke 68 which has its legs extending upwardly throughguide brackets 69 that are secured to the sides of the cross head.Springs Ill surround the legs of the endmost yokes and rest upon thetops of the'brackets 69 that are carried by the cross head, the springsengaging nuts on said legs, so that the yokes are yieldably urgedupwardly. The yokes are all connected in unitary relation by a pipe 1|,so that they move as a unit and the intermediate yokes have gauge nutsI2 threaded thereon to positively limit downward movements of the yokesrelative to the cross head 55. Those extensions of the yokes that carrythe cups-61 are hollow and communicate with the cups and the pipe 1|.

Whenthe cross head 55 is moved downwardly to bring the cups 6! intoengagement with the top sheet of a pack, compressive movement of thecups will cause the airto be forced therefrom beneath the edges of thecups. A check valve I3 (Fig. 6) is provided in the'base of the cups toprevent the air within the cups from being forced back into the bores ofthe yoke in the pipe during application of the cups to the top sheet.

After the cups have been applied to a sheet, as above described, thecranks 58 are actuated to raise the cross head 55 and the top sheetwhich will adhere to the cups 8! by atmospheric pressure. Owing to theinertia of the sheet and the vacuum cups, together with their yokes,springs 10 will be compressed somewhat during the initial stages ofupward movement, the limit nuts 12 on the top of the intermediate yokelegs serving to positively limit the extent to which the springs 18 willbe compressed. After the sheet has been completely lifted or pulled awayfrom the pack and the inertia of the parts overcome, the cups and thesheet will be supported entirely by the springs 10, the stop nuts 12then being clear of the cross head 55.

During the remainder of upward travel of the cross head 55, the sheet isweighed", so that if two sheets stick together, the weight will be suchas to automatically discharge the sheet in one direction, while if asingle sheet of proper weight is being raised by the cups, it will beautomatically discharged in a direction to be fed to rolls. Thisweighing mechanism, as shown more clearly in Figs. 1, 2 and 6, comprisesa rack bar 15 which is secured to the pipe 'II and extends upwardlythrough the cross head 55, and is vertically guided in a bracket 18carried by the cross head. A pinion I1 is secured to a shaft 18 which isjournalled on the bracket 16, and the shaft 18 carries aswitch-operating arm 19 that durin movement of the shaft will actuatecontrol switches 88 and 8|. Normally the arm 19 maintains the switch 8|]in closed position. Upon starting of raising movement by the crank arms58, the cross head 55 will first move upward slightly withoutcorresponding upward movement by the cups, with' the result that therack 15 rotates the pinion TI to cause the arm 19 to release the switch8|) and close the switch 8|. but one sheet is being raised by the cupsat this time, the springs 18 will have sufllcient force to raise thevacuum cups and the single sheet toward the cross head 55, whereby therack 15 is shifted upwardly relative to the cross head,

thus rotating the pinion l5 and swinging the arm back to its normalposition where it closes the switch 80. Upon further movement of thecross head in its upward travel, the sheet is raised above the plane oftake-out conveyors 82, which as hereinafter described, are swung intoposition beneath the sheet-to receive it when it is released from thecups.

Near the end of the upper travel of the cross head, the stem of a valve84 carried by the cross head, engages a stop 85, which opens the valveand admits atmospheric air through a pipe 88 that is connected to thepipe H and thus relieves the vacuum within the cups and permits thesheet to drop upon the conveyors.

The conveyors 82 are disposed adjacent to the path of vertical travel ofthe sheet. Each conveyor comprises a series of rollers 8'! journalled ina channel bar 88, the bars 88 being carried on swinging arms that arehung on rods 90; the rods in turn, at their ends, are supported inbrackets 9|, the brackets being slidably supported on cross rods 82 thatare secured to the framework of the machine. The brackets 9| are keyedagainst rotating movement on the rods 92, as

shown in Fig. 4, and are adjustable longitudinally of the rods 92, beingfastened at set positions thereon by set screws 93. The shafts of therollers 81 have drive connection through bevel gear wheels 94 with ashaft 95, which shaft is journalled in the bearings formed in thebracket 89. The shafts 95 carry sprocket wheels 96 which are driven froma sprocket 91 that is formed unitarily with a sprocket 98. The sprocket98 has driver-chain connection with a sprocket 99 that is formedunitarily with a sprocket I00, the sprocket I having drive-chainconnection with a sprocket IOI on the shaft of a motor I02. The motorI02 is provided with an internal gear-reducing unit at I03; Theunitarily-formed sprocket 99-I00 is journalled on the rod 90. The endbrackets 89 have a crank arm extension I04 that is connected with apiston rod I05 which is operated by a cylinder I06. It will be seen thatas fluid pressure is admitted to the opposite ends of the cylinder I 06alternately, the brackets 89 will be oscillated to move the rollers 81into and out of position beneath a sheet. Before the valve 84 isactuated through raising movement of the cross head, fluid pressure is,admitted to the upper ends of the cylinders I06 to cause the brackets 89to be swung to the position shown in Fig. 1, with the rollers inposition to receive the sheet when it is dropped from the cups. Thismovement of the conveyor 82 to sheet-receiving position is eifected bymeans of timing mechanism which controls raising of the cross head 55and which also controls operation of the knife devices 38.

The timing mechanism is shown in Fig. 11 and comprises a motor-driventimer having a plurality of cams which operate fluid pressure controlvalves I01 to H3 inclusive. When the parts are in position fordescending movement of the cross head to effect engagement by the vacuumcups with the top sheet of a pack, the valve I01 will be in openposition admitting fluid pressure from the line I I4 through a pipe I I5to the lower sides of the cylinders I06, thus holding the arms 89 andthe conveyor rollers 81 in their outermost positions. Similarly, theknife members 38 are held in their retracted positions, because thevalve I08 is in open position, admitting fluid pressure from the line II4 through the pipe 52 to the outer end of the cylinder50, the airsupply for the blast orifices of the knives being closed at valve I09.At this time the valve H0 is open to atmosphere and the valve IIIopened'by its cam to pressure line 4, thus admitting pressure throughthe pipe 86 to the cylinder 64 and causing the rack and pinion to beactuated to rock the crank shaft 59 so as to lower the cross head andthe vacuum cups, the exhaust from the cylinder occurring at this timethrough the pipe 65. At about the time that the cross head has reachedthe limit of its downward movement, the valve I08 is closed, by its cam,to line pressure. and opened to atmosphere, while the valve H2 is openedby its timer cam to the line pressurefrom H4 so that the pistons withinthe cylinders 50 are actuated to move the rollers 40 and the knives 38toward the pack. As the knives begin to penetrate beneath the top sheet,the valve I09 is actuated by its cam to establish communication from theline Ill to the pipe leading to the line 49 and to the interior of theknives, so as to provide the separating blast of air beneath the topsheet, as heretofore referred to.

At this time valve H0 is open to line pressure so that such pressure isadmitted to thefront ratchet wheel I34 secured to the shaft I3I.

end of cylinder 64 to effect reverse movement to the crank shaft 59 andraising of the cross head 55. At the time the sheet has been thus liftedcompletely ofi'the stack, the valve I09 is closed to cut off flow of airto the interiorv of the knives. The knives during the early stages ofraising movement of the sheet, are retained in their projected positionto hold the next succeeding sheet of the pack down. After the top sheethas been lifted clear of the stack, the valve H2 is opened to atmosphereand the valve I08 is opened to line pressure, so as to direct fluidpressure to the front side of the cylinders 50 and retract the knives.

During this raising movement of the cross head 55 and after the sheethas been raised above the plane of the conveyors 82, valve I01 is openedto atmosphere and valve II3 opened to line pressure, so as to admitfluid pressure to the upper sides of the cylinders I06 and thereby rockthe shafts 90, thus swinging the arms 89 and the rollers 81 to theposition shown in Fig. 2 where they can receive the sheet which isreleased, as heretofore described.

A switch I20 is supported in the path of movement of the rack bar 63,whereupon during lowering movement of the cross head, the switch will beengaged by the rack bar and held in open position. During raisingmovement of the cross head, the switch I20 is released by the rack bar63 and thereupon closes under spring pressure, thus establishing a pointin the circuit for the motors I02. At this time if there is only asingle sheet held by the cups, the arm 19 will mainficient expansiveforce to supportthe sheet), and.

the circuit being completed through the switch I20 will causeenergization of the coil I2I of a reversing switch I22, whereupon thecircuit for the motors I02 is completed and the said motors will,through the drive connections, as shown more clearly in Fig. 4, effectrotation of the rollers 81 and discharge of the sheet through takeoutrollers I24. Upon beginning of the next downward movement of the crosshead, the switch I20 will be opened, thus causing stopping of the motorsI02. If there are two sheets held by the suction cups during upwardmovement of the cross head, the weight thereof will hold the springs 10compressed and the arm 19 consequently held in position to maintain theswitch 8| closed (the switch I20 being closed during this upwardmovement, as above explained). A circuit will consequently be completedthrough the coil I of the reversing switch I22, whereupon a pawl arm Iwhich is pivoted on a shaft I3I that is journalled in a bracket I32. Thepawl arm I30 carries a pawl 133 which engages a The shaft I3I carries abevel gear I which drives a -bevel gear wheel I38, that is secured tothe shaft 25. Upon each retractive movement of the piston in thecylinder 64 and the rack bar 83, the bell crank I28 is swung to effectslight rotative movementof the shaft 25 through the connections justdescribed, and hence rotation of the nut 22 of the screw jack, therebyraising the pack slightly so that the underside of the top sheet will bebrought to the plane in which the knives 38 operate. After removal ofall of the sheets of a pack, the table can be quickly returned to itslower position by unlatching the pawl I33 and turning the gear wheel 21to lower the jack.

The apparatus can be adjusted to stacks of various widths, bylongitudinal adjustment of the bars 30 on their supports, toward andaway from the edges of the pack, and by similarly adjusting the brackets9| on the rods 92.

From the foregoing it. will be seen that with the motor-driven timer inconstant operation, the apparatus will automatically move throughrepeated cycles of operation, and during each cycle of operation willeffect separation and lifting of the top sheets from the packs, and whena sheet has been fully raised, the discharge conveyor 82 will be broughtinto position beneath the sheet,

whereupon the sheet will be released and the conveyor set in motion todischarge the sheet. If two sheets are stuck together, the additionalweight on the lifting elements will be such as to cause the conveyor todiscard such sheets in the opposite direction. Upon discharging ofeither one sheet or two sheets which are stuck together, the cycle ofoperations will be automatically repeated. The properly separated sheetswhich are discharged between the rolls I24 can be advanced by otherrolls or conveyor mechanism to rolls where a cold rolling operation isperformed thereon, the apparatus thus serving not only as a sheetseparating and sorting device, but as a feeder for cold rolls.

Referring now to Figs. 12 and 13, I show an apparatus for feeding sheetsone-by-one from a pack mounted in approximately an upright positioninstead of in a horizontal position. In ,this instance the pack ofsheets is represented by the numeral I40, and is supported in aninclined position by brackets I4I that are slidably mounted on a baseI42. Each bracket has threaded connection with an indexing screw I43that is journalled in an upstanding boss on the base I42. The screws I43have bevel connection at I44 with a shaft I45. The shaft I45 is actuatedby a pawl and ratchet mechanism I46, the ratchet arm thereof dependinginto position where it is engaged by a piston rod extension I41 of apiston contained within an operating cylinder I48.

The piston within the cylinder I48 is provided with a piston rod I49 onwhich is formed rack teeth I50 whichengage a gear wheel I5I, that isfixed on a shaft I52, which is journalled on the base I42. Arms I53 aresecured to the rock shaft I52 and at their upper ends carry vacuum cupsI54 in position to be forced against the outermost sheet of the pack I40at points adjacent to the upper edge thereof. Adjacent to the upper edgeof the pack are a series of sheet-separating devices I55 which are ofthe same structure as the separating devices of Figs. 7 to 10 exceptthat they operate in approximately a vertical direction instead ofhorizontally. These devices serve to split the foremost sheet from thevnext of the pack and to direct a blast of air behind it.

A series of conveyor rolls I56 are provided for receiving the sheetsthat are stripped from the pack and carried downwardly by the arms I53into position just above the rolls, at which point the vacuum in thecups is relieved. Each roll I56 has bevel gear connection I58 with ashaft I51 that is constantly driven from a suitable source of power.

Timing mechanism'similar to that shown in Fig. 11 may be employed forcontrolling the supply of fluid pressure to the cylinder I48 thatoperates the swinging arms I53, the cylinders of the separating devicesI55, and the air blast through the separating knives. When the cups I54have been swung to their lower positions indicated by dotted lines inFig. 12, the stems of valves I59 thereof will engage stop screws I60 toopen the valves and admit atmospheric air to the cups, thus relievingthe pressure and releasing the sheets to be carried away by the conveyorrolls I56. During lowering movement of a sheet, the extension rod I4I ofthe piston of the cylinder I48 which actuates the swinging arms I53,will strike the arm of the ratchet device and turn the screw I43slightly so as to advance the pack-supporting brackets a distanceapproximately equal to the thickness of a sheet.

It will be seen that since the vacuum cups all engage the pack at pointsnear only the upper edge thereof, downward swinging movement of the cupscauses removal of the foremost sheet by a peeling or stripping action,so that if the sheets are stuck together somewhat at points below wherethey are initially separated by the knife devices I55, considerableseparating force will thereafter be exerted. simply through the arcuatemovement of the cups, such separating force being, of course, muchgreater and more effective than where a sheet is bodily lifted bysuctional force applied simultaneously at various points throughout thearea thereof.

I claim as my invention:

1. Sheet handling apparatus comprising vacuum cups reciprocablevertically above a sheet pack, the cups being movable into engagementwith successive top sheets of the pack and arranged to lift sheetsvertically from the pack, means for relieving the vacuum in the cupswhen they have reached their upper limit of travel, a conveyor, meansoperable during upward travel of the cups, for shifting the conveyorinto position to receive sheets released from the cups, and meansoperable upon further movement of the cups for removing the conveyor.

2. Sheet handling apparatus comprising vacuum cups arranged to engagethe topmost sheet of a pack and to support the same in a horizontalplane when raised, means for vertically reciprocating said cups, meansfor automatically relieving the vacuum within the cups when they areadjacent to their upward limit of movement, conveyer devices movablelaterally of the path of vertical movement by the cups, and meansactuated through said movement of the cups for moving the conveyors intoand out of position to receive sheets released by the cups.

3. Sheet handling apparatus comprising a vacuum cup device for removingthe outermost sheets successively from a pack, a knife member, and meansfor moving the knife member behind the outermost sheet of a pack, inadvance of sheet removing movement of the vacuum cup, for assisting inseparating said outermost sheet from the rest of the pack.

4. Sheet handling apparatus comprising a v vacuum cup device forremoving the outermost sheets successively from a pack, a knife member,and means for moving the knife member behind the outermost sheet of apack, in advance of sheet removing movement of the vacuum cup,

for assisting in separating said outermost sheet from the rest of thepack, and means for directing a blast of air behind the sheet thusseparated by the knife.

5. Sheet handling apparatus comprising a vacuum cup device for removingthe outermost for directing a blast of air through the edge of the knifewhich enters behind a sheet.

6. Sheet handling apparatus comprising a vacuum cup device for removingthe outermost sheets successively from a pack, a knife member movablebehind the outermost sheet of a pack,

in timed relation to movement of the vacuum cup, for assistinginseparating said outermost sheet from the rest of the pack, and a guidedevice positioned outwardly of the knife, for engaging the face of theoutermost sheet of the pack and serving to guide'the knife blade intoposition behind the rear side of said sheet.

7. The combination with means for removing sheets one-by-one from theexposedside of a pack, of a knife device, a slide block carrying .saiddevice, means for reciprocating said block toward and from the edges ofthe sheets in a pack, and a guide member carried by said slide andpositioned in advance of the knife and to be moved upon the outermostsheet, whereby the knife will be caused to penetrate the packimmediately behind the said sheet.

8. The combination with means for removing sheets one-by-one from theexposed side of a pack, of a knife device, a slide block carrying saiddevice, means for reciprocating said block toward and from the edges ofthe sheets in a pack, a guide roller carried by said slide and havingits axis positioned in advance of the knife and to be moved upon theoutermost sheet, whereby the knife will be caused to penetrate the packimmediately behind the said sheet,

means for maintaining the roller againstdisplacement relative to theslide block when it is moving into position against the face of thesheet, and means effective when the roller has completed its movement ona sheet for releasing the roller to permit it to be swung aside when thesheet is being removed from the pack.

9. Sheet handling apparatus comprising a vertically-movable lifter forsheets, holding elements on the lifter for supporting the sheets inhorizontal position when raised, laterally-spaced sheet-receivingmembers at two opposite sides of the path of lifting movement, and meansoperating in timed relation to lifting movements for moving the saidmembers into and from sheetreceiving position.

10. Sheet handling apparatus comprising a vertically-movable lifter forsheets, holding elements on the lifter for supporting the sheets inhorizontal position when raised, laterally-spaced sheet-receivingmembers at two opposite sides path.

11'. Sheet handling apparatus comprising a vertically-movable lifter forsheets, holding elements on the lifter for supporting the sheets inhorizontal position when raised, sheet-receiving means normallypositioned out of the path of lifting movement, and means automaticallyoperable when the lifter is adjacent to its upper limit of movement, formoving the sheet-receiving means into position beneath a lifted sheet.

12. Sheet handling apparatus comprising a vertically-movable lifter forsheets, holding ele ments on the lifter for supporting the sheets inhorizontal position when raised, sheet-receiving means normallypositioned out of the path of lifting movement, means automaticallyoperable when the lifter is adjacent to its upper limit of movement, formoving the sheet-receiving means into position beneath a lifted sheet,and

means automatically operable to release a lifted sheetfrom said holdingelements.

13. Apparatus for separating sheets from a pack, comprising a knifemember movable behind the outermost sheet of pack, a guide devicepositioned outwardly of the knife, for engaging the face of theoutermost sheet of the pack, and serving to guide the knife member intoposition behind the rear side of said sheet, mechanism for removing theoutermost sheet after entrance of the knife behind the same, and meansfor effecting movement of the said guide device away from the path ofmovement of the sheet during operation of said mechanism.

14. Sheet handling apparatus for removing the outermost sheetssuccessively from a pack, comprising a guide member for engaging theexposed face of the pack, a knife device operatively associated with theguide member, the knife device being so positioned that it will enterbehind the outermost sheet when the guide member moves against theexposed face thereof, means for moving the guide member and the knifedevice toward the pack, means for directing the guide member toward thepack in such path that the sheet-engaging area thereof is disposedrearwardly of the plane of the outermost sheet, and means for deflectingthe guide member against the outermost face of said sheet, to therebymove the knife device to the rearmost plane of the sheet, when the guidemember encounters the pack, whereby continued movement in a directiontoward the pack will cause the blade to penetrate behind the outermostsheet.

15. Sheet handling apparatus for removing the outermost sheetssuccessively from a pack, comprising a guide member for engaging theexposed face of the pack, a knife device operatively associated with theguide member, the knife device being so positioned that it will enterbehind the outermost sheet when the guide member moves against theexposed face thereof, means for moving the guide member and the knifedevice toward the pack, means for yieldably maintaining the guide memberin such path that the sheetengaging area thereof is disposed rearwardlyof the plane of the outermost sheet, means for deflecting the guidemember forwardly and against the outermost face of said sheet, tothereby move the knife device to the rearmost plane of the sheet, whenthe guide member encounters the pack, whereby continued movement in adirection toward the pack will cause the blade to penetrate behind theoutermost sheet, mechanism for removing the outermost sheet afterentrance of the knife behind the same, and means for effecting movementof the guide member out of the path of movement of the sheet duringoperation of said mechanism.

16. Sheet handling apparatus for removing the outermost sheetssuccessively from a pack, comprising a guide member for engaging theexposed face of the pack, a knife device operatively associated with theguide member, the knife device being so positioned that it will enterbehind the outermost sheet when the guide member moves against theexposed face thereof, means for moving the guide member and theknifedevice toward the pack, and means for yieldably maintaining the guidemember in such path that the sheet-receiving area thereof is disposedrearwardly of the plane of the outermost sheet, the forward end of theguide member being of such form thatengagement thereof with the packwill deflect it forwardly of the outermost face of said sheet, tothereby move the knife device into the rearmost plane of the sheet, whenthe guide member encounters the pack, whereby continued movement in adirection toward the pack will cause the blade to penetrate behind theoutermost sheet.

device and the knife device lie in planes inwardly of the plane of sheetseparation, during movement toward the pack, the guide device being ofsuch form that the said member will be deflected outwardly to the planeof the said face, when the guide device enters upon a pack.

LLEWELLYN HOPKINS.

